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Thermally Conductive Liquid Silicone Rubber Adhesives

Q: Can thermally conductive adhesive India replace both the thermal pad and the mechanical fastener?

Yes, in many applications. A cured KE adhesive bond simultaneously transfers heat, provides electrical insulation and mechanically fixes the component — eliminating the need for separate screws, clips or pads. However, the joint is permanent; rework requires cutting or peeling the cured silicone, which may damage delicate components. For field-serviceable designs, use a combination of mechanical fastener and thermal pad instead.

Q: What surfaces does the thermally conductive adhesive India bond to without a primer?

Condensation-cure KE grades bond primerlessly to clean aluminium, most metals, glass and silicone rubber with good peel and lap-shear strength. Addition-cure grades typically achieve better bond strength to ceramics and coated metals with an appropriate primer. Both types require surfaces to be free of oil, dust and moisture — clean with isopropyl alcohol before application. For specific substrate-adhesion data, request the technical datasheet from Pantronics India.

Q: How long does the thermally conductive adhesive India take to reach full strength?

Condensation-cure (RTV) grades typically achieve handling strength within 30–60 minutes at 23°C and reach full mechanical and thermal properties after 7 days at 23°C / 50% RH. Addition-cure grades accelerated at 60–80°C in a conveyor oven reach full cure in 30–60 minutes — enabling production throughput at standard SMT post-reflow oven temperatures. Contact Pantronics India for process integration support.

The most versatile thermally conductive adhesive India range — Shin-Etsu KE series. One-component paste and liquid adhesives that cure to thermally conductive silicone rubber, simultaneously bonding, insulating and dissipating heat. Condensation cure (RT) and heat-cure addition variants for power electronics, ECUs and sensor housings.

0.85–4.0

W/m·K

V-0

UL94 (all grades)

1-component

Condensation or Addition

4.0 W/m·K

KE-1891 (highest)

Overview

What Are KE-Series Thermal Adhesives?

KE-Series adhesives are one-component, thermally conductive silicone rubber compounds supplied as pastes or liquids. Applied to a component by dispenser or spatula, they fill irregular shapes completely before curing to form a permanently bonded, thermally conductive elastomeric layer.

Condensation cure types (KE-4918-WF, KE-4961-W, KE-4962-W) cure at room temperature using ambient moisture. They release an alcohol byproduct during cure and should be used in environments with some ventilation or moisture access. Addition cure types (KE-1867, KE-1891) cure rapidly at 120°C with no byproduct gas — ideal for inline oven curing on production lines.

Conforms to any component shape — paste fills irregular gaps before curing
Condensation cure: room temperature, no oven required; requires moisture and ventilation
Addition cure: 120°C × 1 h, no byproduct gas, predictable cure profile for production lines
Simultaneously bonds, fixes, electrically insulates and dissipates heat
KE-1891 reaches 4.0 W/m·K — highest conductivity in the adhesive range, matching G-787
UL94 V-0 on all five grades; dielectric strength 23–27 kV/mm

Application Scenes

Where Phase Change Materials Are Used

Compact Power Adapter / Charger

KE-4961-W or KE-4962-W condensation-cure adhesive is dispensed over transformer, FET and diode components inside compact laptop and phone charger housings — filling all irregular gaps and bonding the assembly while eliminating the need for pad-cutting.

Irregular-Shape Hybrid ICs & RF Modules

KE-1867 and KE-1891 addition-cure adhesives bond hybrid ICs, RF power modules and custom-shaped power dies to aluminium or copper heat spreaders, providing both the permanent mechanical bond and the thermal interface in a single dispensed layer.

EV Inverter Control Board Bonding

KE-1891 (4.0 W/m·K) addition-cure adhesive bonds control board components to the EV inverter housing, providing high thermal conductivity, strong adhesive bond and UL94 V-0 compliance in a single process step within the oven-cure production cycle.

LED Fixture Assembly — Uneven Array

Where LED emitters are of varying heights and a flat pad cannot maintain contact with all elements simultaneously, KE condensation-cure adhesive is dispensed across the array — the paste self-levels to fill every gap before curing to a permanent thermally conductive bond.

Datasheet

General Properties — PCS SeriesGeneral Properties — KE Series Adhesives

Properties after cure — JIS R 2616 (thermal), JIS K 6249 (mechanical), JIS K 6850 (lap shear)

Parameter	KE-4918-WF	KE-4961-W	KE-4962-W	KE-1867	KE-1891
Thermal conductivity (W/m·K)	0.85	1.6	2.4	2.2	4.0
Cure type	1-component condensation	1-component addition
Appearance (uncured)	White paste	White paste	White paste	Gray liquid	Grayish white paste
Byproduct gas	Alcohol	Alcohol	Alcohol	None	None
Curing conditions	23°C / 50%RH × 7 days	120°C × 1 h
Density at 23°C (g/cm³)	1.68	2.34	2.65	2.92	3.06
Hardness, Durometer A	80	80	88	75	96
Tensile strength (MPa)	3.5	3.9	4.4	2.1	5.3
Elongation at break (%)	50	60	30	60	10
Volume resistivity (TΩ·m)	4.5	1.0	1.0	1.2	3.4
Dielectric breakdown (kV/mm)	27	24	25	23	25
Lap-shear strength Al/Al (MPa)	1.0	0.7	0.8	0.8	0.8
Flame resistance UL94	V-0	V-0	V-0	V-0	V-0
LMW siloxane (ppm)	<300	<300	<300	<300	<300

Grade Selector

Choosing the Right Thermally Conductive Adhesive India Grade

KE-series thermally conductive adhesives India offer two cure mechanisms — room-temperature condensation cure and heat-accelerated addition cure — with conductivities from 0.9 to 1.3 W/m·K. Use this guide to match the cure type to your production process.

Parameter	Condensation Cure (RTV)	Addition Cure (Heat)
Cure trigger	Atmospheric moisture; RT, 7 days to full cure	Heat 60–80°C, 30–60 min to full cure
By-product	Trace acetic acid or alcohol (grade-dependent)	No by-product — pure addition cure
Deep-section cure	Limited — cures from surface inward	Full — cures uniformly through depth
Primerless adhesion	Good to aluminium, silicone, glass	Excellent to most metals and ceramics with primer
Thermal conductivity (W/m·K)	0.9–1.2	1.0–1.3
Best for	Low-volume / manual assembly, field repair	High-volume production lines, oven or IR cure

Note on conductivity: At 0.9–1.3 W/m·K, KE thermally conductive adhesive India grades are optimised for bonding — conductivity is significantly higher than unfilled adhesive (~0.2 W/m·K) but lower than dedicated thermal pads or gap fillers. Where both bonding and maximum heat transfer are needed, specify the adhesive type for bonding and a higher-conductivity pad or gap filler for thermal transfer if the geometry permits both.

FAQ

Thermally Conductive Adhesive India — Common Engineer Questions

Can thermally conductive adhesive India replace both the thermal pad and the mechanical fastener?

Yes, in many applications. A cured KE adhesive bond simultaneously transfers heat, provides electrical insulation and mechanically fixes the component — eliminating the need for separate screws, clips or pads. However, the joint is permanent; rework requires cutting or peeling the cured silicone, which may damage delicate components. For field-serviceable designs, use a combination of mechanical fastener and thermal pad instead.

What surfaces does the thermally conductive adhesive India bond to without a primer?

Condensation-cure KE grades bond primerlessly to clean aluminium, most metals, glass and silicone rubber with good peel and lap-shear strength. Addition-cure grades typically achieve better bond strength to ceramics and coated metals with an appropriate primer. Both types require surfaces to be free of oil, dust and moisture — clean with isopropyl alcohol before application. For specific substrate-adhesion data, request the technical datasheet from Pantronics India.

How long does the thermally conductive adhesive India take to reach full strength?

Condensation-cure (RTV) grades typically achieve handling strength within 30–60 minutes at 23°C and reach full mechanical and thermal properties after 7 days at 23°C / 50% RH. Addition-cure grades accelerated at 60–80°C in a conveyor oven reach full cure in 30–60 minutes — enabling production throughput at standard SMT post-reflow oven temperatures. Contact Pantronics India for process integration support.